1. Field of the Invention
The present invention relates to an infrared radiation lamp.
2. Description of the Related Art
Different types of infrared radiation lamps are known to the art. These lamps are based on a tungsten filament or tungsten wire enclosed in a light bulb. This filament emits a large amount of infrared radiation when heated by an electric current. Such lamps, however, deliver a relatively low radiation power, for instance a power of about 1.5-2 W/cm.sup.2.
There is a need to generate much higher power concentrations, and then particularly on small surfaces. For instance, there is a need to produce a power concentration of 80-90 W/cm.sup.2 on a surface of only some few square centimeters in area. It has not earlier been possible to achieve such power concentrations.
There is also a need to reach such high power concentrations over larger surfaces of different configurations, such as round surfaces and elongated, rectangular surfaces, for instance. In addition to obtaining a high power concentration, there is also a need to be able to vary the power concentration over the surface concerned.
The reason why a high concentration is required is often because it is desired to heat a product rapidly during manufacture. An example of needing to rapidly heat small surfaces is found in the application of plastic caps on packaging units, where only the surface of the caps shall be quickly heated to melting temperature, for instance to a temperature of 300-400.degree. C. An example of larger surfaces is found in the heating of wafers in electronic manufacturing processes, where the higher power shall be delivered to the peripheral parts of the wafer as opposed to the central part thereof.
The present invention satisfies the requirement of a high power concentration in respect of infrared radiation lamps.
The present invention is not restricted to any particular use, and can be applied in many different fields.